Railway-traffic-controlling apparatus



Nov. 9 1926.

N )NVENTORI u U 2- M a Al i-W R. A. M CANN RAILWAY TRAFFIC .CONTROLLING APPARATUS Filed July 10, 1926 Patented Nov. 9, 1926.

dTATEd RONALD A. MCCANN, OF S'WISSVALE, PENNSYLVANIA, .ASSIGNOR TO THE UNION SWITCH & SIGNAL COMPANY, OF SWISSVA LE, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA.

EAILWAY-TRAFFIC-CONTROLLING APPARATUS.

Application filed July 10, 1926. Serial No. 121,645.

My invention relates to railway traific controlling apparatus, and particularly to apparatus of the type wherein cars 01' trains are governed by energy supplied thereto from the trackway. More specifically, the present invention relates to the trackway portion of such apparatus.

T will describe one form of apparatus embodying my invention, and will then point out the novel features thereof in claims.

The accompanying drawing, is a diagrammatic view showing one form of apparatus embodying my invention.

Referring to the drawing, the reference characters 1 and 1 designate the track rails of a railway along which traflic normally moves in the direction indicated by the arrow. These rails are divided by insulated joints 2 into a plurality of sections, of which only three complete sections, DE, EF and FG, are shown in the drawing.

Located adjacent the entrance end of each section is a roadside signal designated by the reference character S with an exponent corresponding to the location. Each of these signals in the form here shown comprises two semaphore arms 3 and 4:, and the indications given by each signal are as follows: When both arms are in the horizontal or zero position, the signal indicates stop; when the lower arm i is horizontal and the upper arm 3 is in the inclined or position, the signal indicates proceed prepared to stop at next signal; when the lower arm 4 is in the vertical or 90 position and the upper arm 3 is inclined, the signal indicatesproceed prepared to slow down at next signal; and when the lower arm 4; is horizontal and the upper arm 3 is in the vertical or 90 position, the signal indicates proceed.

Associated with each signal is a track relay designated by the. reference character R with the same exponent as that applied to the signal, each track relay comprising a winding 17 connected across the rails of the associated section, and a second winding 18 connected with the two terminals B and C of a suitable source of alternating current which is. not shown in the drawing. It will he seen,'therefore, that each track relay is responsive to reversals of the relative polarity of the current supplied to its track winding 17.

Also associated with each signal is a line relay designated by the reference character H with the same exponent as that applied to the signal. I

Associated with each track relay R is a track repeating relay A, the circuit for this relay being fromterminal B, through contact ll of the associated track relay R and the winding of relay A to terminal C. It follows that each relay A will be: energized whenever the associated track relay is energized, and will be de-energized whenever the associated track relay is de-energized.

The lower arm 4 of each signal is provided with a single controlling circuit, whereas the upper arm 3 of each signal is provided with two circuits which may be termed the 45 circuit and the 90 circuit, respectively. The 45 circuit for arm 3 is from terminal B, through contact 10 of track relay R, back .point of cont-act 14- of relay H, wire 45, operating mechanism of arm 3, wire 27, and contact 8 to terminal C. This circuit is closed whenever track relay R is energized in either direction and line relay H is ole-energized. The 90 circuit for arm 3 is from terminal B, through contact 10, front point of contact 14, wire 90, operating mechanism of arm 3, wire 27, and contact 8 to terminal C. This circuit is, of course, closed when relay R is energized in either direction and line relay H is energized. The operating circuit for arm t is from terminal B, through right-hand point of contact 9 of relay R, circuit controller 5, operating mechanism of arm 4., wire 27, and contact 8 to terminal C. This circuit is closed only when relay R is energized in normal direction and arm 3 is in the 45 position.

The line relay H associated with each signal is controlled by a pole-changing relay J for the signal next in advance, and, consequently, the control of relayJ will first be explained. Referring to location E, relay J is provided with a circuit which passes from terminal B, through right-hand point of contact 9 of relay R circuit controllers 6 and 22 in multiple, and winding of relay J to terminal C. Circuit controller 6 is closed when arm 3 is in the 90 position but not in the horizontal or the 45 position, and circuit controller 22 is closed when arm 4 is in the 90 position but not in the horizontal position. It follows that relay J will. be energized when signal S indicates proceed or proceed prepared to slow down at next signal.

Line relay H is controlled by contact 21 of relay J in such manner that the line relay is energized r de-energized according as relay J is energized or deenergized, the circuit being obvious from the drawing.

Track circuit current is supplied to the rails of each section by a transformer designated T with an exponent corresponding to the location. Tneseoondary of this transformer is connected directly across the track rails, whereas the primary is supplied with track circuit current through a polechanger P operated by the upper arm 3 of the adjacent signal S. The operation of this pole-changer is such that track circuit current of normal relative polarity is supplied to the rails when arm 3 is in the 45 or position, but that track circuit current of reverse relative polarity is supplied to the rails when arm 3 is in the horizontal position.

As shown in the drawing, a train W occupies the track section immediately to the right of point G, so that signal S indicates stop. Track circuit current of reverse rel atiVe polarity is therefore supplied to section FGr, so that track relay R is energized in the reverse direction. Pole-changing relay J is de-energized because its circuit is open at both circuit controllers 6 and 22, and so the line relay H is de-energized. The only circuit which is closed for signal S is the 45 circuit for arm 3 and so this signal indicates proceed prepared to stop at next signal. Arm 3 of signal S being in the 45 position, thetrack circuit current supplied to section E-F is of normal relative polarity, so that track relay R is energized in normal direction. Line relay H is de-energized, however, because pole-changing relay J is de-energized, and so signal S indicates proceed prepared to slow down at next signal. Arm 3 of signal S being in the 45 position, the track circuit current supplied to section D-E is of normal relative polarity, so that relay R is energized in the normal direction. The pole-changing relay J is energized because arm 4 of signal S is in the vertical position, and so the line relay H is energized. Signal S therefore indicates proceed.

Each section is also provided with means for supplying thereto an additional train controlling current which may be termed a loop or a local current and for this purpose three resistances 23, 24 and 25 are connected across the rails of the section at the entrance end, an intermediate point K, and the exit end of the section, respectively. Loop current is supplied to each section by a transformer 15. Referring particularly tosection FG, the circuit for the secondary of transformer 15? is from the lower terminal of this secondary through back contact 28 of relay H resistance 23, track rails 1 and 1 resistance 2% and circuit controller 7 to the upper terminal of the secondary of transformer 15 That is to say, signal S being in the stop position loop current is supplied to section FG between points F and K only. When signal S gives any other indication, the loop circuit will be as follows: from the lower terminal of the secondary of transformer 15 through back contact 28 of relay A resistance 23, at the entrance end of the section, resistance 25 at the exit end, contact 12 of relay A and circuit controller 7 to the upper terminal of the transformer second ary.

The primary of transformer 15 is supplied with current through pole-changer P and also through pole-changing contacts 19 and 20 on relay J The primary circuit for this transformer therefore includes two pole-changers in series, and these polechangers operate to control the relative polarity of the loop current in the following manner: Signal S being at stop, polechanger P is reversed and relay J is deenergized, so that the pole-changing contacts 19 and 20 are also reversed. These two reversals result in loop current of normal relative polarity being supplied to the rails of section FG between points F and K. In section Ill-F, pole-changer P is normal and the pole-changing contacts of relay .1 F are reversed, so that loop current of reverse relative polarity is supplied to section E-F throughout the entire length of the section. In section D li pole-changer P is normal, and relay J is energized, so that loop current of normal relative polarity is supplied to the rails through-out the length of the section.

The-apparatus shown in the drawing is intended for co-operation with train-carried mechanism adapted to receive energy in ductively from the track rails, which mechanism operates in the following manner: When the train receives track circuit current of normal relative polarity and loop current of normal relative polarity, a proceed indication is given aboard the train. When the train receives track circuit current of reverse relative polarity and loop current of normal relative polarity, or track circuit current of normal relative polarity and loop current of reverse relative polarity, a cantion indication is given aboard the train. When the supply of either track circuit current or loop current is discontinued, a stop indication is given aboard the train.

I will now assume that the section immediately to the right of point G is occupied by a train WV, as shown in the drawing, and

that a following train equipped with the mechanism hereinbefore described passes through the stretch of track shown in the drawing. In section DE the following train will receive a proceed indication, because this section is supplied with track circuit current and loop current which are both of normal relative polarity. In section EF the track circuit current is still of normal relative polarity, but the loop cur rent is of reverse relative polarity, so that acaution indication will be given aboard the train. current is of reverse relative polarity, but the loop current is of normal relative polarity, so that a caution indication will be given aboard the train from point F to point K. Upon passing point K the train will receive a stop indication because of the absence of loop current.

It will be seen from the foregoing that the first section in the rear of an occupied sect-ion receives track circuit current of reverse relative polarity and loop current of normal relative polarity; the second section in the rear of an occupied section receives track circuit current of normal relative polarity and loop current 01" reverse relative polarity, and all other track sections receive track circuit and loop current both of normal relative polarity.

Although I have herein shown and described only one form of apparatus embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. In combination, a plurality of successive sections of railway track, means for supplying alternating track circuit current of reverse relative polarity to the first section in the rear of an occupied section and of normal relative polarity to all other sections, and means for supplying loop train control ling alternating current of reverse relative polarity to the second section in the rear of an occupied section and of normal relative polarity to all other sections.

2. In combination, a plurality of successive sections of railway track each provided with a track circuitincluding the rails connected in series and a loop circuit including the rails connected in multiple, two polechangers for each section cont-rolled by traffic conditions in advance of the section,

In section F-G the track circuitmeans for supplying alternating current to the track circuit for each section through one only of said pole-changers, and means for supplying alternating current to the loop circuit for each section by both polechangers tor the section.

3. In combination, a plurality of successive sections of railway track each provided with a track circuit including the rails connected in series and a loop circuit including the rails connected in multiple, two polechangers for each section controlled by traffic conditions in advance of the section, means for supplying alternating current to one of said circuits for each section through one only of said polechangers for the section, and means for supplying alternating current to the other circuit for each section through both pole-changers for the section.

4. In combination, a plurality of successive sections of railway track each provided with a track circuit including the rails connected in series and a loop circuit including the rails connected in multiple, two polechangers for each section one of which is in normal or reverse position according as the section next in advance is unoccupied or occupied and the other of which is in normal position when the two sections next in advance are unoccupiedbut in reverse position when either such section is occupied, means for supplying alternating current to one of said circuits for each section through one only of said pole-changers for the section, and means for supplying alternating current to the other circuit for each section through both pole-changers for the sect-ion.

5. In combination, a plurality of successive sections of railway track each provided with a track circuit including the rails connected .in series and a loop circuit including the rails connected in multiple, two polechangers for each section one of which is in normal or reverse position according as the section next in advance is unoccupied or occupied and the other of which is in normal position when the two sections next in advance are unoccupied but in reverse position when either such section is occupied, means for supplying alternating current to the track circuit for each section through only the first of said pole-changers for the section, and means for supplying alternating current to the loop circuit for each section through both pole-changers for the section.

In testimony whereof I afliX my signature.

RONALD A. MCCANN. 

